Originally Posted by
captaincowpants
They make sky scrapers out of steel, because it is flexible. Steel will stretch.
Implying that steel is flexible, but titanium is not? That is not true.
Flexibility can be defined by Young's Modulus (Modulus of Elasticity), or how much a material will stretch in response to stress:
Steel, Structural ASTM-A36: 200 GPa
Titanium Alloy: 105-120 GPa
Titanium is at least 66%
more flexible than steel.
Originally Posted by
captaincowpants
Make a spring out of ti, post again when you are finished.
Did that already, decades ago. Ti springs are fairly common on spacecraft, where weight and reliability is at a premium. Back when my job was space hardware, I had to analyze a Ti spring design for an oscillating mirror. The flexibility of Ti was useful, it meant that the spring didn't have to be stupid thin (and thus more delicate and harder to machine).